Memory chipmaker Kioxia Holdings Corp. has overtaken Toyota Motor Corp. to become Japan's most valuable company, marking a dramatic shift in the nation's corporate hierarchy. The surge reflects investor enthusiasm for semiconductor companies amid the artificial intelligence boom that's reshaping global tech markets.

Shares jumped 7.6% Friday, pushing Kioxia's market capitalization above ¥44 trillion ($274 billion). This milestone comes just 18 months after the company's market debut, demonstrating how quickly investor sentiment can shift toward high-growth technology sectors.

Toyota Motor Corp., which had previously lost the top spot briefly to SoftBank Group Corp., closed with a market value of ¥43.8 trillion. The figures include treasury shares across all companies, providing a standardized comparison of market worth.

The transition signals that Japanese investors increasingly favor semiconductor exposure over traditional manufacturing. As AI demand accelerates, memory chip companies like Kioxia represent the new engines of growth in Japan's economy, challenging the dominance of automotive giants that ruled for decades.